The law requires that infectious waste, in particular medical waste, be shredded such that it is not recognizable or reusable, and above all such that it can be highly sterilized. To that end, it is known to use a shredding and sterilizing machine for such waste, comprising an upper hopper for receiving waste, a median shredding compartment, and a lower tub for receiving, sterilizing and discharging shredded waste.
The median shredding compartment includes a shredder formed from a parallel series of contrarotating knives, the knives in one series alternating with counter-knives. The knives in one series cooperate with the counter-knives in another, adjacent series, and vice versa.
The waste tending not to be captured by the knives of the shredder and to remain in the hopper, it has in particular been considered to equip the hopper with a flexible sheath for receiving and coating the waste, traveling with the waste toward the shredder and intended to be shredded with the waste; it has also been considered to equip the hopper with a steerable shaft for pushing the waste toward the shredder.
The median shredding compartment and the lower tub must be sterilized using pressurized steam between each waste treatment cycle, which means tightly closing the opening that exists between the bottom of the hopper and the median shredding compartment. This closing is done using a sliding hatch.
The existing machines of this type are globally satisfactory, but may nevertheless still be perfected.
Indeed, the aforementioned steerable shafts are not always very effective and involve the presence of an operator. The sliding hatch risks trapping waste between it and its sliding seat when it closes, which leads to a risk of incomplete closing of this hatch and the exertion of unwanted additional and repeated forces on the means for actuating the hatch. Furthermore, fragments of waste tend to rise more or less from the shredder and accumulate in said seat, consequently requiring frequent cleaning of said seat. Furthermore, the sliding hatch makes it necessary to provide means for disinfecting the hopper that are separate from the means for disinfecting and sterilizing the median shredding compartment and the lower receptacle, which also makes the structure and operation of the device more complex.